Surfacing machine



y 1937. G. M. CURTIN SUI-{FACING MACHINE Filed May 11, 1935 5 Sheets$heet l INVENTOR 6160265 Cu/PT/AA ATORNEY y 6, 1937. G. M. c'uia'rm SURFACING MACHINE Filed May 1 1, 1955 5 Sheets-Sheet 2 INVENTOR 5227665 M 60/? 77/V.

ATTORNEY y .6; 1937- G. M. CURTIN SURFACING MACHINE Filed May 11, 1955 5 Sheets-Sheet 4 INVENTOR 65026:" M Kw? rm ATTORNEY y 9 1937- G. M. CURTIN ,086,516

SURFACING MACHINE Filed May 11, 1935 5 Sheets-Sheet 5 Patented July 6, 1937 SURFAGING momma George M. Curtin, Gloversville, N. Y., assignor -of one-half to Behr-Manning Corporation, Watervliet, N. Y., a corporation-of Massachusetts, and one-half to Curtin, Hebert Company, Inc.,.Gloversville, N. Y., a corporation of New York Application May 11, 1935, Serial No. 20,963

10 Claims.

4 This invention relates to surfacing machines and, with regard to its more specific features, to machines for surfacing leather and other sheet material.

One object of the invention is to provide a machine of the type indicated adapted efliciently to surface material which varies in thickness. Another object of the invention is to permit extreme niceties of adjustment of the machine. Another object of the invention is automatically to remove or to return the hides after a treatment thereof. Another object of the invention is to prevent the wrapping of hides or other material around the rollers or any of them. Another object of the invention is to remove static electricity from the machine parts, especially the rollers, as fast as it accumulates. Another object of the invention is to remove dust and abradant material from the abradant drum, the rollers, and from the machine. Another object of the invention is to provide an improved machine of the type described m my United States Letters Patent No. 1,975,349. Other objects will be in part obvious'or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combination of elements, and arrangements of parts, as will be exemplifled in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings, in which is shown one of various possible embodiments of the mechanical features of this invention,

Figure 1 is a view partly in front elevation and partly in section of a machine embodying the invention;

Figure 2 is a plan view of the machine;

Figure 3is a side elevation of the machine as seen from the right-hand side thereof;

Figure 4 is a vertical sectional View ofv the machine, the section being taken on the line 44 of Figure 2;

Figure 5 is a fragmentary detailed view on an enlarged scale showing the mounting of the air D 1 Figure 6 is a plan view of the frame of the machine together with the abradant drum and a raversing mechanism for the air blast pipe;

Figure '7 is a vertical sectional view illustrating the traversing mechanism of Figure 6;

Figure 8 is a fragmentary view, partly in section, showing the supporting and guiding rollers for the air-blast pipe.

Figure 9 is a cross sectional view, on an enlarged scale, of the abradant drum, the rolls and the conveyer belt, showing a hide being operated upon by the machine.

Referring to Figures 1, 2, 3 and 4, I provide a pair of side frames in and II which, as shown, may be of inverted- U-shape thus collectively constituting the four legs of the machine together with a pair-of horizontal portions extending from front to back thereof. I further provide a pair of fore and aft connecting frame 10 members 12 and i3 which may be of similar shape, and as best shown in Figure 1 may be U-shaped in cross-section. I further provide at the front and the back of the machine respectively X-shaped frame members l4 and I5 con- 15 meeting the legs of the U-shaped side frames 'IO and I I. The foregoing constitutes a rigid but comparatively light frame for the mounting of the mechanism now to be described.

Referring now to Figure 1, a vertical plate 20 extends between the frame members l0 and I2 and. is fastened to them and constitutes a support for a pair of similar triangular members 29 which are preferably integral with a horizontal support 22 for a motor base 23 of an electric motor 24 which constitutes the machine prime mover. The armature shaft 25 of the motor is connected by means of a clutch 26 to a horizontal shaft 21 extending between journal blocks 28 mounted on top of the side frames l0 and H 30 respectively. In order to position the shaft 21 in both axial directions, collars 29 may be provided outside the journal blocks 28 as better shown in Figure 2. As the clutch 26 is of the constantly coupled type but allows for slight axial movement and vibration of the armature shaft 25 or any precession thereof, the shaft 21 is fixed to rotate on a true axis without side motion and at high speed.

Rigidly mounted upon the shaft 2'I is a drum 30 which, so far as certain features of the invention are concerned, might be of many different types, such for example as a set-up abrasive drum of a type long used for the surfacing of leather, but I prefer to use a drum of the general type described in the copending 'application of Seymour J. Hallsted, Serial No.

21,733, filed May 16, 1935, adapted for receiving a covering of abrasive paper spirally wound thereon and provided with means for tightening wound is indicated at 3!, and I prefer to use be predetermined.

paper coated with silicon carbide grain as I have achieved excellent results thereby, although it should be understood that paper or cloth coated with any other. suitable abrasive grain such as aluminum oxide, garnet, flint, quartz or emery may be used.

Referring now to Figures 3 and 4, the front part of the top of each side frame IO and II is milled or otherwise suitablysurfaced to provide a smooth slideway and upon the surfaces are mounted a pair of similar slides 35 each having an inside apron 36 and an outside apron 31 adapted to bear against the inside of the side frame members and the outside of the outside frame members respectively; thus the slides 35 are mounted for movement in a horizontal direction fore and aft of the machine and are maintained in position. Grooves 38 in the outside of the frame members ill and II are engaged by tongues 39 extending inwardly from the aprons 31 in order to prevent the slides 35 from rising at either end.

Still referring to Figures 3 and 4, extending from the inside of the horizontal portion of the inside frame members 10 and H are studs 48 upon. which'are mounted bell crank levers 4| having arms extending vertically and horizontally; in the vertical arm of each bell crank lever is a slot 42 and in these slots 42 are studs 43 fastened to the aprons 36. The horizontal arms of the bell crank levers 4| are connected by means of pins 44 to links 45 extending downwardly to levers 46, the links 45 being connected to the levers by means of pins 41. The levers 46 are freely mounted on a shaft 49 which extends between brackets 50 bolted to the under side of the frame members l2 and B respectively.- Projecting laterally from the rear ends of the levers Mi are square pins 5| each adapted to receive one or a plurality of detachable weights 52. Connecting the front portions of the levers 46 is a wooden plank treadle member 53.

From the foregoing description it will be seen that when the operator steps upon the treadle platform 53 the slides 35 are moved forwardly, and when he removes-his foot from the treadle platform 53 the weights 5| cause the slides 35 to move rearwardly of the machine. Preferably the .shaft 48 is not a rock shaft, that is to say levers 46 are not keyed thereto but are independent and are simply pivotally mounted thereon, so that the levers 46 are independently movable and although they are connected by a single platform member 53, it is shown as made of wood and will therefore warp, and by stepping on the right-handside thereof there is a tendency for the right-hand slide 35 to move farther to the front than the left-hand slide 35 and vice versa. Thus within limits the slides 35 need not occupy exactly similar positions, although there is a tendency for them to do so when the operator steps upon the center of the treadle plank 53. I provide forwardly extending stop arms 55 preferably integral with the slides 35 and having depending portions 56 through which extend screws 51 having hand wheels 58 thereon. The other ends of the screws 51 are adapted to contact with stationary stop portions 59 integral "with the side frames l0 and II respectively, and by means of these screws 51 the forward position of the slides 35 may be varied and accurately determined, and as aforesaid slight differences in their respective positions may Still referring to Figures 3 and 4, uprising from the rear (with relation to the whole machine) end of the slides 35 are journal members 60 mounting a shaft 6| which extends parallel to the shaft 21 and in front of it. Secured to' the shaft El and between the journals 68 is a rubber covered roller 62; as shown in Figuresl and 2 the rubber covered roller 62 is preferably about the same length as the drum 30 and coterminus .with it.

In order that there shall be no binding of the shaft 6| in the journals 60, these journals are swiveled on the slides 35. Referring to Figures 2 and 51, the journal members 68 have vertical trunnions 63 which rest in vertical bores of an-.

a countershaft 68 which is mounted in a journal 68 fastened to the frame member II. The countershaft 68 extends to the other side of the side frame member H and has fastened to it on the ,inside end a pinion gear 10 which meshes with a large gear attached to a second countershaft 12 mounted in a journal member 13 likewise fastened to the top of the frame member l3. The countershaft 12 extends also to the outside of the side frame H and as better shown in Figure 1 has there fastened to it a'double V-pulley II which is connected by V-belts 16 to a large double V-pulley fastened to the outside of the shaft 6|. Thus the shaft 6| is rotated continuously and ma direction opposite to that of the shaft 21 and at a very much slower angular velocity and the rubber roller 62 has a very much lower peripheral velocity than the abrasive drum Ill. 5

A variation in the angular velocity of the rubber roller 62 may be effected by shifting'the belt 66 on the step pulleys 65 and 61. The drive for the rubber roller 62 is not affected by the movement thereof fore and aft of the machine within wide limits.

The rubber roller 62 is a feed roller to feed hides or other material to be surfaced, to the abrasive covered drum 30. To facilitate the manipulation of skins or hides or the like, I provide a horizontal table whose upper surface is in a plane close to the horizontal plane, tangent to the top of therubber roller 62, and which table 60 is carried by the slides 35 as by means of a pair of supports 8| affixed to the front of each slide 35 as shown in Figures 1 and 3. The supports, 8| may be in the form of Z-irons and enough play is. introduced where they are attached to the table 80 (preferably of wood) to allow the aforesaid variation in angularposition of the axis of the roller 62. 7

Referring now to Figures 1 and 4, I provide a pinch roller preferably of steel which cooperates with the rubber roller 62 to feed the hides or other material. The pinch roller 85 also serves in combination with the features of the mounting of the roller 62 already described,to position the feed roller 62 to the best advantage for the surfacingpf hides of unequal thickness. The machine in this respect is automatically or selfadjusting. Referring now to Figure 1, the pinch roller 65 is mounted upon a shaft 86 which in turn is mounted in journal portions 61 which, as better shown in Figures 3 .and 4, are located on the front of long arms 88 that are articulated on 9| that, as shown in Figures 3 and 4, are adjust-' ably secured to the side frame members I0 and II respectively. The standards 5| rest solidly upon the frames Ill and I I, having offset portions 92 through slots in which clamping bolts 92a pass. Thus the pinch roller 85 is revolubly carried by the machine and its position may be changed by swinging it in an arc around the pins 89.

In the surfacing of hides a half a thousandth of an inch is a significant dimension and insomuch as according to this invention the position of the pinch roller 85 determines the amount of material removed it is highly desirable that the position of the pinch roller be adjustable within precision limits. I have provided screws 93 extending vertically through the arms 88 having heads 94 whereby they may be adjusted, all as shown in Figure 3, and the arms 88 are drilled and tapped, and the lower ends of the screws 93 contact the tops of plates 95 secured to the tops of upward extensions 96 of the portions 92, these extensions also having a surface resting solidly on the top portions of the side frame members l0 and H. By turning the heads 94 of the screws 93 the arms 88 can be raised or lowered.

In prior surfacing machines of this general type the pinch roller has been spring-pressed against the rubber roller. In such machines, when a thick portion of the material being treated ex isted at one side thereof, the thin places would escape treatment altogether. According to my invention, in one aspect thereof, I secure a more even treatment of material which may vary in thickness by automatically positioning the rubber feed roller 52 to allow for such variation in thickness. This I accomplish by securing the pinch roller 85 against vertical movement once its position has been determined, and accordingly I provide bolt-headed screws 98 extending through the arms 88 into the plates 95, into tapped holes therein. Thus the screws 93 and E38 constitute, in combination with the plates 95, mecision adjustment and clamping means to adjust the pinch roller 85 accurately, and the fore and aft position of the roller is determined by the adjustment at the bolts 92a. Thus it will be seen that insomuch as the pinch roller is fined, if a. thick portion of hide comes between it and the rubber roller, the rubber roller will be backed off thus increasing the clearance between the rubber roller and the abrasive drum.

Before proceeding with the description of other features of the invention it will facilitate under standing of the machine to describe its mode of operation. The operator stands at the front of the machine which is at the left in Figures 3 and 4, and placing an untreated hide on the table 89 before throwing the switch to energize the motor 24, he loosens the screw 98, raises the pinch roller by means of the screws 93, steps on the treadle platform 53 and introduces the leading edge of the hide between the rubber feed roller 62 and the abrasive roller 3il. Each type of finish to be secured and each variety of hide surfaced may require a different pressure, and the machine provides means for varying the pressure between the feed roller 52 and the abrasive roller 30 in the form of weights 52 which are placed on the bars 5!, and knowing the material to be treated the operator will select the desired number of weight units 52 and place them in position as indicated in Figures 3 and 4. The

operator then turns both hand wheels 58 counter-clockwise to allow the feed roller 52 to press the hide against the abrasive roller 30, and then turns each clockwise to set the screws 5i in contact with the stops 59. The screws 93 are now manipulated by means of the heads 5 to allow the pinch roller 85 to rest upon the upper surface of the hides, and then the screws 93 are turned down to hold the pinch roller 85 in this position of adjustment. The operator then steps upon the treadle platform 53 and withdraws the hide. In setting up the machine an unfinished hide should be selected which is of fairly uniform thickness, and of about the same thickness as a number of hides to be treated.

The motor 26 may now be started and when the leading edge of a hide is introduced between the pinch roller '85 and the rubber roller 62 the machine does the rest. See Figure 9, in which the hide being treated is indicated by the numeral 206. Should the right-hand part of the hide be thicker than the left-hand part, for example, in-

somuch as the mounting for the pinch roller 85 is rigid, the rubber feed roller 82 is automatically backed off more on the right-hand side and this permits the hide to be buffed by the machine without stalling or without other damage.

I provide means for removing the hides from the machine and delivering them either at the back or the front thereof as may be desired.

When two operators are working on a machine it is convenient to have the hides removed therefrom at the back of the machine. When a single operator is working on the machine it is more convenient to have the treated hides returned to the operator.

the machine.

In some classes of work, it is an advantage to change the relative rotational directions of the sanding drum and the rubber roll. Normally, the direction relation is as shown in Fig.1: 1 where the rolls operate in opposite directions at different speeds, but I can reverse the direction of rotation of the rubber roll by crossing belt 66 which may be desirable for some buffing operations. When operating as just specified. with the drum and rubber roller rotating anguiarly in the same direction, that is peripherally oppositely, the operator pushes down the treadle, inserts the skin, hide or other sheet material so that it lies between the rubber roll and the sanding drum. The treadle is then released and the hide pulled toward the operator. The hide Especially is this so where it is desired to surface each hide more than once in is then turned around and buffed on the other end.

pair of journal brackets N15 to the inside of the X-frarne members M and these brackets support a shaft M6 to which is secured a roller (of wood, if desired) ifll. Similarly as shown in Figures 2, 3 and a, li secure brackets "38 to the inside of the X-frame members [5; and these brackets have horizontal slideways 109 in which are mounted sliding journal boxes H0 supporting a shaft ill to which is fastened a roller I I2 like the roller lfll. A plurality of tape belts H3 extend around the rollers I81 and H2 in parallel relation, and they may be tightened by moving the slidable journal blocks H0. screws H5 extending through the inside ends of the brackets I08 and abutting the blocks H6 being provided for this purpose, lock nuts H6 being provided to set the screws H5 in the desired position of adjustment. Thus a plurality of endiess belts or tapes 3 are provided in a horizontal plane extending nearly from front to back of the machine and below the rollers 30 and 62 and in position to receive hides delivered downwardly after being surfaced by the abrasive roller 30.

Referring now to Figure l, for driving these belts H3 I provide a pulley IIB on the inside end of the shaft I2 and a pulley II9 on the right-hand end of the shaft I06, these pulleys I I8 and I I9 being connected by a belt I20. When the belt I20 is a straight belt as shown, the upper sides of the belts M3 are moving from front to back of the machine, but to cause the belts II3 to travel in the reverse direction-to carry the hides to the front of the machine simply cross the belt I20.

Animal hides are more or less dielectric substances or poor conductors of electricity and all of the commonly used abrasive substances are good dielectrics and insulators, including aluminum oxide, silicon dioxide, garnet and silicon carbide, and when two substances which are not good conductors are rubbed together electricity is generated of high potential and of the type generally referred to as static. As the abrasive grains on the paper 3| of the drum 30 cut the hide, a particular charge is generated on the abrasive grains and the opposite charge on the hides, and as the hides are a fair dielectric the opposite charge is induced on the side of the hides next to the-rubber of the roller 82 which in turn induces an opposite charge on the roller 02. Without knowing what the sign of the charge on the abrasive grains is, if this could be assumcd to be positive, the charge on the side of the hides being cut would be negative, the charge on the other side of the hides would be positive and the charge on the rubber roll 52 would be negative. The result is that the hides have a tendency to hug the abrasive drum 30 and, in some cases, the rubber feed roller 62. This fact has been known before but so far as I am aware I am the first one to discover what I believe to be the true explanation.

As in my Patent No. 1,975,349 I prefer to remove the hides from the abrasive roller 30 by means of blasts of air and, as shown in Figures 2, 3 and 5, I'may use a plurality of nozzles I2I projecting from a pipe I22 extending between standards 9| and supported thereby, being clamped in position by plates I23, and the air being supplied by any suitable blower such as indicated in the patent referred to. I prefer to direct the blast of air downwardly as this assists gravity in removing the hides from the drum 30.

I desire also to reduce the attraction between hides and drum, so far as may be done, and accordingly I affix a pair of standards I26 to the journal members 28 these standards extending upwardly and supporting between them wires I21 having metal fibers I28 projecting therefrom. The wires I21 may be twisted wires having the metal fibers projecting therefrom in the manner of chenille, and the ends ofthe metal fibers hang close to the surface of the abrasive drum 30 and remove the charge of electricity as fast as it is formed conveying it by way of the standards I26, which are metal, right into the machine frame whence it is d ssipated. Likewise I neutralize the charge on the roller 52 by means of similar metallic fibers, tinsel or chenille I30 extending from twisted wires I3I or the like fastened to the slides 35. The removal of the charge from the rubber roller 62 causes hide dust which otherwise adheres to the roller 62 to drop from it and furthermore, it reduces tendency of the hides to wrap around the rubber roller. As the feed roller revolves relatively slowly it has been found in prior machines to collect dust, which I believe to adhere thereto by reason of the static charge referred to, and at all events the "provision of the means described causes the dust to drop off the roller 62. It will be readily seen that this collection of dust which caked onto a roller was a serious detriment in prior machines for it destroyed the adjustment between the feed roller and the abrasive drum, and in the present machine with its automatic adjustment of the position of the feed roller 62 it is highly desirable to avoid a caking of dust upon the feed roller 62.

For removing dust produced by the machine I provide a dust collecting funnel member I35 made out of sheet metal and located below the tapes or belts II3. I prefer to use tapes H3 rather than a solid apron in order to allow the dust to be carried downwardly into the dust collecting funnel 435 which connects to pipes I36 in the bottom thereof. These pipes I36 are connected to the exhaust end of a suitable blower associated with a suitable dust collector of any type, such blowers and dust collectors being well known in the pneumatic arts and being located preferably apart from the machine and driven by a separate motor. In fact, one dust collector and blower may service a number of machines according to the present invention.

In order to improve the lasting qualities of the abrasive covering 3|, I may use the mechanism shown in Figures 6, 7 and 8. This mechanism includes an air pipe I40 which is traversed back and forth to direct jets of air all over the abrasive drum -30, such blasts being high velocity blasts. By directing the air through small openings in the pipe I40 and thus securing high velocity blasts and at the same time traversing them, I have found that I can effectively remove comminuted material which otherwise collects in the interstices between grain, and I can thus keep the abrasive free cutting for a longer time. Referring now to Figures 6, 7 and 8, the shaft I2, inside of the'gear II is provided with a second pulley I4I adjacent the pulley IIII. A belt I42 extends to a pulley I43 and drives it, the pulley I43 being fastened to a shaft I44 journaled in a journal bracket I45 which is fastened to the side frame II and which has journal portions I46 and I41 for the shaft I44. On the shaft I44 is secured a worm' I48 which is in mesh with a worm wheel I49 secured to a cross shaft I50 journaled in journals II and I52 upstanding from the journal bracket I45. Fastened to the end of the shaft I50 is a crank I53 which is connected by means of a link I54 to a pin I55 proj'ecting from a metal strap member I56 that extends around the pipe I40 and is secured thereto by means of abolt I51. As the pulley I43 revolves it drives the worm I48 which turns the worm wheel I49 slowly thus slowly turning the crank I53-which reciprocates the pin I55 and therefore the pipe I40.

The pipe I40 has a cap I60 at one end and is connected to a flexible hose I 6| at the other end by means of a coupling I82. The pipe I40 is supported as shown in Figures 6 and 8'between grooved rollers I63 and I 64, there being two of each arranged in pairs and supported by brackets I65 secured to any convenient part of the machine such as the X-frame members I5.

Thus the pipe I60 is slowly reciprocated and it has a great number of verv fine holes therein.

These holes are preferably drilled from the in- .side, for example by drilling a larger hole from the other side of the pipe and then using a small drill to drill the air holes, thereafter plugging up the first set of holes. By drilling the holes in this manner they are tapered toward the outlet which produces a higher velocity blast of air. Preferably I use a No. 40 drill for these holes, and their axes are such as to direct the blasts of air downwardly, for example about 30 dog. from the horizontal, Figure 7. The pipe M0 should be located as close to the drum 30 as is practicable mechanically.

This mechanism not only prolongs the life of the coated abrasive material, but also gives a more uniform rate of out throughout the life thereof and eliminates scratches which otherwise result when coated abrasive is filled with foreign material which is loaded thereon unevenly. In the absence of means to clean the coated abrasive, I have found that it becomes loaded unevenly, even accumulating in spots and streaks. It is a fact that such unevenly loaded abrasive scratches and mars material being treated.

Although I have referred chiefly to hides as the material being treated, this was by way of example only, and the machine of the present invention is particularly effective to surface any sheet material. For example it has been used successfully. in the surfacing of sheet rubber, paper, cork fiber, newspaper press blankets; and by the expression hides" I intend to include skins, kips, chamois; and by surfacing I include shaving, sanding, bufling; and the machine is universal so that it can be used for either roughing or finishing operations.

It will thus be seen that there has been provided by this invention an apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many-changes might be made in the embodiment above' set forth, it is to be understood that all matter hereinbefore set forth, or shown in the accompanying drawings, is to be interpreted as illustrative and not in a limiting sense.

I claim:-

. i. In apparatus 61' the class described, the combination with an abradant drum, means to rotate said abradant drum at a high peripheral velocity, 9. feed roller, and means to rotate said feed roller in the opposite direction of rotation at a relatively slow peripheral velocity, of a pair of journals for said feed roller one at each end thereof and each individually movable in a direetion generally towards and away from said abradant drum, separate means urging each of said journals toward said abradant drum, a roller whose axis projected to the plane of the axes of the first named roller and the drum lies between them, means for mounting said last named roller to permit free rotation thereof comprising a pair of journals, 9. pair of pivotally mounted supports for said journals so located that said journals may be moved in, a direction generally normal to the aforesaid plane, and a pair of individual clamping means, one for the free end of each of said supports, whereby to secure said journals in adjusted position.

2. In apparatus of the class described, in combination, an abradant drum, a feed roller, electrostatic removing means for removing dust from said feed roller, and a dust collector comprising funnel means adapted for connection to air exhaust apparatus.

3. In apparatus of the class described, in combination, an abradant drum mounted for rotation on a fixed axis, a feed roller positioned to contact said abradant drum, a pair of journals for said feed roller one at each end thereof, a pivotal mounting for each of said journals to permit either end of the feed roller to move toward and away from the abradant drum, and a pinch roller parallel to the abradant drum and between it and the feed roller and mounted on a fixed axis.

4. In apparatus of the class described, in combination, an abradant drum mounted on a fixed axis, a feed roller mounted on an axis movable in the common plane of its axis and the axis of the abradant drum both angularly and toward and away from said abradant drum, a pinch roller mounted on an axis which is movable in like manner as said feed roller but substantially in a plane normal to the aforesaid plane and clamping means for clamping said pinch roller in adjusted position.

5. In apparatus of the class described, in combination, an abradant drum, a feed roller, journals for said feed roller each pivotally mounted on an axis substantially perpendicular to the common plane of said abradant drum and said feed roller and each of said journals being movable toward and away from the axis of said abradant drum, a pinch roller adjustable in a direction substantially normal to said plane, and means for clamping said pinch roller in adusted position.

6. In apparatus of the class described, the combination with an abradant drum, means to rotate said abradant drum at a high peripheral velocity, a feed roller, and means to rotate said feed roller in the opposite direction of rotation at a relatively slow-peripheral velocity, of means urging said feed roller toward said abradant drum, a second roller, and means mounting said second roller for free rotation comprising a pair of pivoted arms, journals in said arms, and clamping means to clamp said arms in adjusted position.

7. In apparatus of the class described, the combination with an abradant drum, means to rotate said abradant drum at a high peripheral velocity,

a feed roller, and means to rotate said feed roller in the same direction of rotation at a relatively slow peripheral velocity, of a pair of journals for said feed roller one at each end thereof and each individually movable in a direction generally towards and away from said abradant drum, separate means urging each of said journals toward said abradant drum, a roller whose axis projected to the plane of the axes of the first named roller and the drum lies between them, and means for mounting said third roller to permit free rotation thereof comprising a pair of journals indi- J vidually movable in a direction generally normal to separate the hides from said abradant drum, means below said air blast means comprising a funnel adapted for connection to air exhaust apparatus to remove dust from the machine, said air blast means serving also to drive dust into said funnel, and an endless conveyer comprising a plurality of spaced elements located between said funnel and said abrasive drum to convey hides out of the machine, allowing dust to move downwardly into the funnel.

GEORGE M. CUR'I'IN. 

